Add well-known OIDs to System.Formats.Asn1

This adds most of the OIDs that are read or written during the execution of any of the
crypto tests or SslStream tests as a well-known pattern of bytes and a pre-allocated/
const/interned string.

Reading a well-known OID drops from ~300ns to ~60ns and saves on allocating the output
string, and possibly an `int[]` in BigInteger for large-RID OIDs, while increasing the
cost for a less well-known OID by about 40ns.

Writing a well-known OID drops from ~1200ns to ~90ns, and increases the cost for a less
well-known OID by only about 10ns.

For purposes of this initial list, an oid was well-known if (more or less):
* It was the output of ReadObjectIdentifier more than twice, and
* It was not a facetious/test value (e.g. 0.0), and
* It was not a vendor-specific Certificate Practices Statement; or
* It was an obviously linked OID potentially skewed out by our test data
  * e.g. EcdsaWithSha512 would be automatically included by closeness to EcdsaWithSha256.

diff --git a/src/libraries/System.Formats.Asn1/src/System.Formats.Asn1.csproj b/src/libraries/System.Formats.Asn1/src/System.Formats.Asn1.csproj
index fe14e8c..4888658 100644 (file)
--- a/src/libraries/System.Formats.Asn1/src/System.Formats.Asn1.csproj
+++ b/src/libraries/System.Formats.Asn1/src/System.Formats.Asn1.csproj
@@ -53,6 +53,7 @@ System.Formats.Asn1.AsnWriter</PackageDescription>
     <Compile Include="System\Formats\Asn1\SetOfValueComparer.cs" />
     <Compile Include="System\Formats\Asn1\TagClass.cs" />
     <Compile Include="System\Formats\Asn1\UniversalTagNumber.cs" />
+    <Compile Include="System\Formats\Asn1\WellKnownOids.cs" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == '$(NetCoreAppCurrent)'">

diff --git a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnDecoder.Oid.cs b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnDecoder.Oid.cs
index 4410633..fac90e1 100644 (file)
--- a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnDecoder.Oid.cs
+++ b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnDecoder.Oid.cs
@@ -53,8 +53,27 @@ namespace System.Formats.Asn1
             out int bytesConsumed,
             Asn1Tag? expectedTag = null)
         {
-            // TODO: Inline this call when it won't cause a PR/diff problem.
-            return ReadObjectIdentifier(source, ruleSet, expectedTag, out bytesConsumed);
+            // T-REC-X.690-201508 sec 8.19.1
+            ReadOnlySpan<byte> contents = GetPrimitiveContentSpan(
+                source,
+                ruleSet,
+                expectedTag ?? Asn1Tag.ObjectIdentifier,
+                UniversalTagNumber.ObjectIdentifier,
+                out int consumed);
+
+#if NETCOREAPP
+            string? wellKnown = WellKnownOids.GetValue(contents);
+
+            if (wellKnown is not null)
+            {
+                bytesConsumed = consumed;
+                return wellKnown;
+            }
+#endif
+
+            string ret = ReadObjectIdentifier(contents);
+            bytesConsumed = consumed;
+            return ret;
         }
 
         private static void ReadSubIdentifier(
@@ -172,20 +191,8 @@ namespace System.Formats.Asn1
             CryptoPool.Return(tmpBytes, bytesWritten);
         }
 
-        private static string ReadObjectIdentifier(
-            ReadOnlySpan<byte> source,
-            AsnEncodingRules ruleSet,
-            Asn1Tag? expectedTag,
-            out int totalBytesRead)
+        private static string ReadObjectIdentifier(ReadOnlySpan<byte> contents)
         {
-            // T-REC-X.690-201508 sec 8.19.1
-            ReadOnlySpan<byte> contents = GetPrimitiveContentSpan(
-                source,
-                ruleSet,
-                expectedTag ?? Asn1Tag.ObjectIdentifier,
-                UniversalTagNumber.ObjectIdentifier,
-                out int consumed);
-
             // T-REC-X.690-201508 sec 8.19.2 says the minimum length is 1
             if (contents.Length < 1)
             {
@@ -278,7 +285,6 @@ namespace System.Formats.Asn1
                 contents = contents.Slice(bytesRead);
             }
 
-            totalBytesRead = consumed;
             return builder.ToString();
         }
     }

diff --git a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnWriter.Oid.cs b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnWriter.Oid.cs
index fe66477..c8ab9e9 100644 (file)
--- a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnWriter.Oid.cs
+++ b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/AsnWriter.Oid.cs
@@ -59,6 +59,19 @@ namespace System.Formats.Asn1
         {
             CheckUniversalTag(tag, UniversalTagNumber.ObjectIdentifier);
 
+#if NETCOREAPP
+            ReadOnlySpan<byte> wellKnownContents = WellKnownOids.GetContents(oidValue);
+
+            if (!wellKnownContents.IsEmpty)
+            {
+                WriteTag(tag?.AsPrimitive() ?? Asn1Tag.ObjectIdentifier);
+                WriteLength(wellKnownContents.Length);
+                wellKnownContents.CopyTo(_buffer.AsSpan(_offset));
+                _offset += wellKnownContents.Length;
+                return;
+            }
+#endif
+
             WriteObjectIdentifierCore(tag?.AsPrimitive() ?? Asn1Tag.ObjectIdentifier, oidValue);
         }
 

diff --git a/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/WellKnownOids.cs b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/WellKnownOids.cs
new file mode 100644 (file)
index 0000000..cbcd6b3
--- /dev/null
+++ b/src/libraries/System.Formats.Asn1/src/System/Formats/Asn1/WellKnownOids.cs
@@ -0,0 +1,423 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#if NETCOREAPP
+namespace System.Formats.Asn1
+{
+    internal static class WellKnownOids
+    {
+        private static ReadOnlySpan<byte> DSA =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x38, 0x04, 0x01, };
+        private static ReadOnlySpan<byte> DSAWithSha1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x38, 0x04, 0x03, };
+        private static ReadOnlySpan<byte> EC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x02, 0x01, };
+        private static ReadOnlySpan<byte> EcPrimeField =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x01, };
+        private static ReadOnlySpan<byte> EcChar2Field =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x02, };
+        private static ReadOnlySpan<byte> Secp256r1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x03, 0x01, 0x07, };
+        private static ReadOnlySpan<byte> ECDSAWithSha1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x01, };
+        private static ReadOnlySpan<byte> ECDSAWithSha256 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x02, };
+        private static ReadOnlySpan<byte> ECDSAWithSha384 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x03, };
+        private static ReadOnlySpan<byte> ECDSAWithSha512 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x04, };
+        private static ReadOnlySpan<byte> RSA =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, };
+        private static ReadOnlySpan<byte> RSAWithSha1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x05, };
+        private static ReadOnlySpan<byte> RSAOAEP =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x07, };
+        private static ReadOnlySpan<byte> MGF1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x08, };
+        private static ReadOnlySpan<byte> OaepPSpecified =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x09, };
+        private static ReadOnlySpan<byte> RSAPSS =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0A, };
+        private static ReadOnlySpan<byte> RSAWithSha256 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0B, };
+        private static ReadOnlySpan<byte> RSAWithSha384 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0C, };
+        private static ReadOnlySpan<byte> RSAWithSha512 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0D, };
+        private static ReadOnlySpan<byte> PbeWithMD5AndDESCBC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x03, };
+        private static ReadOnlySpan<byte> PbeWithSha1AndDESCBC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0A, };
+        private static ReadOnlySpan<byte> PbeWithSha1AndRC2CBC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0B, };
+        private static ReadOnlySpan<byte> Pbkdf2 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0C, };
+        private static ReadOnlySpan<byte> PasswordBasedEncryptionScheme2 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0D, };
+        private static ReadOnlySpan<byte> Pkcs7Data =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x01, };
+        private static ReadOnlySpan<byte> Pkcs7SignedData =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x02, };
+        private static ReadOnlySpan<byte> Pkcs7EnvelopedData =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x03, };
+        private static ReadOnlySpan<byte> Pkcs7EncryptedData =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x06, };
+        private static ReadOnlySpan<byte> Pkcs9EmailAddress =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x01, };
+        private static ReadOnlySpan<byte> Pkcs9ContentType =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x03, };
+        private static ReadOnlySpan<byte> Pkcs9MessageDigest =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x04, };
+        private static ReadOnlySpan<byte> Pkcs9SigningTime =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x05, };
+        private static ReadOnlySpan<byte> Pkcs9CounterSigner =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x06, };
+        private static ReadOnlySpan<byte> Pkcs9Challenge =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x07, };
+        private static ReadOnlySpan<byte> Pkcs9ExtensionRequest =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x0E, };
+        private static ReadOnlySpan<byte> Pkcs9SMimeCapabilities =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x0F, };
+        private static ReadOnlySpan<byte> TstInfo =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x01, 0x04, };
+        private static ReadOnlySpan<byte> SigningCertificateAttr =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x0C, };
+        private static ReadOnlySpan<byte> SignatureTimeStampAttr =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x0E, };
+        private static ReadOnlySpan<byte> SigningCertificateV2Attr =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x2F, };
+        private static ReadOnlySpan<byte> Pkcs9FriendlyName =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x14, };
+        private static ReadOnlySpan<byte> LocalKeyId =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x15, };
+        private static ReadOnlySpan<byte> Pkcs12X509CertType =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x16, 0x01, };
+        private static ReadOnlySpan<byte> Pkcs12TripleDes =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x03, };
+        private static ReadOnlySpan<byte> Pkcs12Rc2Cbc128 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x05, };
+        private static ReadOnlySpan<byte> Pkcs12Rc2Cbc40 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x06, };
+        private static ReadOnlySpan<byte> Pkcs12KeyBag =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x01, };
+        private static ReadOnlySpan<byte> Pkcs12ShroudedKeyBag =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x02, };
+        private static ReadOnlySpan<byte> Pkcs12CertBag =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x03, };
+        private static ReadOnlySpan<byte> Pkcs12SecretBag =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x05, };
+        private static ReadOnlySpan<byte> Pkcs12SafeContentsBag =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x06, };
+        private static ReadOnlySpan<byte> MD5 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, };
+        private static ReadOnlySpan<byte> HMACSHA1 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x07, };
+        private static ReadOnlySpan<byte> HMACSHA256 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x09, };
+        private static ReadOnlySpan<byte> HMACSHA384 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x0A, };
+        private static ReadOnlySpan<byte> HMACSHA512 =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x0B, };
+        private static ReadOnlySpan<byte> RC2CBC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x03, 0x02, };
+        private static ReadOnlySpan<byte> TripleDESCBC =>
+            new byte[] { 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x03, 0x07, };
+        private static ReadOnlySpan<byte> Pkcs12KeyProviderName =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x11, 0x01, };
+        private static ReadOnlySpan<byte> KeyIdentifier =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x11, 0x03, 0x14, };
+        private static ReadOnlySpan<byte> UserPrincipalName =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x14, 0x02, 0x03, };
+        private static ReadOnlySpan<byte> DocumentNameAttr =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x58, 0x02, 0x01, };
+        private static ReadOnlySpan<byte> DocumentDescriptionAttr =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x58, 0x02, 0x02, };
+        private static ReadOnlySpan<byte> KeyPurposeTlsServer =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x01, };
+        private static ReadOnlySpan<byte> KeyPurposeTlsClient =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x02, };
+        private static ReadOnlySpan<byte> KeyPurposeCodeSign =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x03, };
+        private static ReadOnlySpan<byte> KeyPurposeEmailProtection =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x04, };
+        private static ReadOnlySpan<byte> KeyPurposeTimestamping =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x08, };
+        private static ReadOnlySpan<byte> KeyPurposeOcspSigner =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x09, };
+        private static ReadOnlySpan<byte> Pkcs7NoSignature =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x02, };
+        private static ReadOnlySpan<byte> OCSP =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x01, };
+        private static ReadOnlySpan<byte> OcspNonce =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x01, 0x02, };
+        private static ReadOnlySpan<byte> CAIssuers =>
+            new byte[] { 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x02, };
+        private static ReadOnlySpan<byte> SHA1 =>
+            new byte[] { 0x2B, 0x0E, 0x03, 0x02, 0x1A, };
+        private static ReadOnlySpan<byte> DES =>
+            new byte[] { 0x2B, 0x0E, 0x03, 0x02, 0x07, };
+        private static ReadOnlySpan<byte> Secp384r1 =>
+            new byte[] { 0x2B, 0x81, 0x04, 0x00, 0x22, };
+        private static ReadOnlySpan<byte> Secp521r1 =>
+            new byte[] { 0x2B, 0x81, 0x04, 0x00, 0x23, };
+        private static ReadOnlySpan<byte> CommonName =>
+            new byte[] { 0x55, 0x04, 0x03, };
+        private static ReadOnlySpan<byte> SerialNumber =>
+            new byte[] { 0x55, 0x04, 0x05, };
+        private static ReadOnlySpan<byte> CountryOrRegionName =>
+            new byte[] { 0x55, 0x04, 0x06, };
+        private static ReadOnlySpan<byte> Locality =>
+            new byte[] { 0x55, 0x04, 0x07, };
+        private static ReadOnlySpan<byte> StateOrProvinceName =>
+            new byte[] { 0x55, 0x04, 0x08, };
+        private static ReadOnlySpan<byte> OrganizationName =>
+            new byte[] { 0x55, 0x04, 0x0A, };
+        private static ReadOnlySpan<byte> OrganizationalUnit =>
+            new byte[] { 0x55, 0x04, 0x0B, };
+        private static ReadOnlySpan<byte> OrganizationIdentifier =>
+            new byte[] { 0x55, 0x04, 0x61, };
+        private static ReadOnlySpan<byte> SubjectKeyIdentifier =>
+            new byte[] { 0x55, 0x1D, 0x0E, };
+        private static ReadOnlySpan<byte> KeyUsage =>
+            new byte[] { 0x55, 0x1D, 0x0F, };
+        private static ReadOnlySpan<byte> SubjectAlternativeName =>
+            new byte[] { 0x55, 0x1D, 0x11, };
+        private static ReadOnlySpan<byte> BasicConstraints =>
+            new byte[] { 0x55, 0x1D, 0x13, };
+        private static ReadOnlySpan<byte> CrlNumber =>
+            new byte[] { 0x55, 0x1D, 0x14, };
+        private static ReadOnlySpan<byte> AuthorityKeyIdentifier =>
+            new byte[] { 0x55, 0x1D, 0x23, };
+        private static ReadOnlySpan<byte> Aes128Cbc =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x02, };
+        private static ReadOnlySpan<byte> Aes192Cbc =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x16, };
+        private static ReadOnlySpan<byte> Aes256Cbc =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x2A, };
+        private static ReadOnlySpan<byte> Sha256 =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, };
+        private static ReadOnlySpan<byte> Sha384 =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, };
+        private static ReadOnlySpan<byte> Sha512 =>
+            new byte[] { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, };
+        private static ReadOnlySpan<byte> CabForumDV =>
+            new byte[] { 0x67, 0x81, 0x0C, 0x01, 0x02, 0x01, };
+        private static ReadOnlySpan<byte> CabForumOV =>
+            new byte[] { 0x67, 0x81, 0x0C, 0x01, 0x02, 0x02, };
+
+        internal static string? GetValue(ReadOnlySpan<byte> contents)
+        {
+            return contents switch
+            {
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x38, 0x04, 0x01, ] => "1.2.840.10040.4.1",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x38, 0x04, 0x03, ] => "1.2.840.10040.4.3",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x02, 0x01, ] => "1.2.840.10045.2.1",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x01, ] => "1.2.840.10045.1.1",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x02, ] => "1.2.840.10045.1.2",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x03, 0x01, 0x07, ] => "1.2.840.10045.3.1.7",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x01, ] => "1.2.840.10045.4.1",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x02, ] => "1.2.840.10045.4.3.2",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x03, ] => "1.2.840.10045.4.3.3",
+                [ 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x04, 0x03, 0x04, ] => "1.2.840.10045.4.3.4",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, ] => "1.2.840.113549.1.1.1",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x05, ] => "1.2.840.113549.1.1.5",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x07, ] => "1.2.840.113549.1.1.7",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x08, ] => "1.2.840.113549.1.1.8",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x09, ] => "1.2.840.113549.1.1.9",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0A, ] => "1.2.840.113549.1.1.10",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0B, ] => "1.2.840.113549.1.1.11",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0C, ] => "1.2.840.113549.1.1.12",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x0D, ] => "1.2.840.113549.1.1.13",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x03, ] => "1.2.840.113549.1.5.3",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0A, ] => "1.2.840.113549.1.5.10",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0B, ] => "1.2.840.113549.1.5.11",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0C, ] => "1.2.840.113549.1.5.12",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x05, 0x0D, ] => "1.2.840.113549.1.5.13",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x01, ] => "1.2.840.113549.1.7.1",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x02, ] => "1.2.840.113549.1.7.2",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x03, ] => "1.2.840.113549.1.7.3",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x06, ] => "1.2.840.113549.1.7.6",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x01, ] => "1.2.840.113549.1.9.1",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x03, ] => "1.2.840.113549.1.9.3",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x04, ] => "1.2.840.113549.1.9.4",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x05, ] => "1.2.840.113549.1.9.5",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x06, ] => "1.2.840.113549.1.9.6",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x07, ] => "1.2.840.113549.1.9.7",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x0E, ] => "1.2.840.113549.1.9.14",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x0F, ] => "1.2.840.113549.1.9.15",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x01, 0x04, ] => "1.2.840.113549.1.9.16.1.4",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x0C, ] => "1.2.840.113549.1.9.16.2.12",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x0E, ] => "1.2.840.113549.1.9.16.2.14",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x10, 0x02, 0x2F, ] => "1.2.840.113549.1.9.16.2.47",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x14, ] => "1.2.840.113549.1.9.20",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x15, ] => "1.2.840.113549.1.9.21",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x16, 0x01, ] => "1.2.840.113549.1.9.22.1",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x03, ] => "1.2.840.113549.1.12.1.3",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x05, ] => "1.2.840.113549.1.12.1.5",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x01, 0x06, ] => "1.2.840.113549.1.12.1.6",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x01, ] => "1.2.840.113549.1.12.10.1.1",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x02, ] => "1.2.840.113549.1.12.10.1.2",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x03, ] => "1.2.840.113549.1.12.10.1.3",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x05, ] => "1.2.840.113549.1.12.10.1.5",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x0C, 0x0A, 0x01, 0x06, ] => "1.2.840.113549.1.12.10.1.6",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, ] => "1.2.840.113549.2.5",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x07, ] => "1.2.840.113549.2.7",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x09, ] => "1.2.840.113549.2.9",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x0A, ] => "1.2.840.113549.2.10",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x0B, ] => "1.2.840.113549.2.11",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x03, 0x02, ] => "1.2.840.113549.3.2",
+                [ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x03, 0x07, ] => "1.2.840.113549.3.7",
+                [ 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x11, 0x01, ] => "1.3.6.1.4.1.311.17.1",
+                [ 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x11, 0x03, 0x14, ] => "1.3.6.1.4.1.311.17.3.20",
+                [ 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x14, 0x02, 0x03, ] => "1.3.6.1.4.1.311.20.2.3",
+                [ 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x58, 0x02, 0x01, ] => "1.3.6.1.4.1.311.88.2.1",
+                [ 0x2B, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x58, 0x02, 0x02, ] => "1.3.6.1.4.1.311.88.2.2",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x01, ] => "1.3.6.1.5.5.7.3.1",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x02, ] => "1.3.6.1.5.5.7.3.2",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x03, ] => "1.3.6.1.5.5.7.3.3",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x04, ] => "1.3.6.1.5.5.7.3.4",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x08, ] => "1.3.6.1.5.5.7.3.8",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x03, 0x09, ] => "1.3.6.1.5.5.7.3.9",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x06, 0x02, ] => "1.3.6.1.5.5.7.6.2",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x01, ] => "1.3.6.1.5.5.7.48.1",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x01, 0x02, ] => "1.3.6.1.5.5.7.48.1.2",
+                [ 0x2B, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x02, ] => "1.3.6.1.5.5.7.48.2",
+                [ 0x2B, 0x0E, 0x03, 0x02, 0x1A, ] => "1.3.14.3.2.26",
+                [ 0x2B, 0x0E, 0x03, 0x02, 0x07, ] => "1.3.14.3.2.7",
+                [ 0x2B, 0x81, 0x04, 0x00, 0x22, ] => "1.3.132.0.34",
+                [ 0x2B, 0x81, 0x04, 0x00, 0x23, ] => "1.3.132.0.35",
+                [ 0x55, 0x04, 0x03, ] => "2.5.4.3",
+                [ 0x55, 0x04, 0x05, ] => "2.5.4.5",
+                [ 0x55, 0x04, 0x06, ] => "2.5.4.6",
+                [ 0x55, 0x04, 0x07, ] => "2.5.4.7",
+                [ 0x55, 0x04, 0x08, ] => "2.5.4.8",
+                [ 0x55, 0x04, 0x0A, ] => "2.5.4.10",
+                [ 0x55, 0x04, 0x0B, ] => "2.5.4.11",
+                [ 0x55, 0x04, 0x61, ] => "2.5.4.97",
+                [ 0x55, 0x1D, 0x0E, ] => "2.5.29.14",
+                [ 0x55, 0x1D, 0x0F, ] => "2.5.29.15",
+                [ 0x55, 0x1D, 0x11, ] => "2.5.29.17",
+                [ 0x55, 0x1D, 0x13, ] => "2.5.29.19",
+                [ 0x55, 0x1D, 0x14, ] => "2.5.29.20",
+                [ 0x55, 0x1D, 0x23, ] => "2.5.29.35",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x02, ] => "2.16.840.1.101.3.4.1.2",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x16, ] => "2.16.840.1.101.3.4.1.22",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x2A, ] => "2.16.840.1.101.3.4.1.42",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, ] => "2.16.840.1.101.3.4.2.1",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, ] => "2.16.840.1.101.3.4.2.2",
+                [ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, ] => "2.16.840.1.101.3.4.2.3",
+                [ 0x67, 0x81, 0x0C, 0x01, 0x02, 0x01, ] => "2.23.140.1.2.1",
+                [ 0x67, 0x81, 0x0C, 0x01, 0x02, 0x02, ] => "2.23.140.1.2.2",
+               _ => null,
+            };
+        }
+
+        internal static ReadOnlySpan<byte> GetContents(ReadOnlySpan<char> value)
+        {
+            return value switch
+            {
+                "1.2.840.10040.4.1" => DSA,
+                "1.2.840.10040.4.3" => DSAWithSha1,
+                "1.2.840.10045.2.1" => EC,
+                "1.2.840.10045.1.1" => EcPrimeField,
+                "1.2.840.10045.1.2" => EcChar2Field,
+                "1.2.840.10045.3.1.7" => Secp256r1,
+                "1.2.840.10045.4.1" => ECDSAWithSha1,
+                "1.2.840.10045.4.3.2" => ECDSAWithSha256,
+                "1.2.840.10045.4.3.3" => ECDSAWithSha384,
+                "1.2.840.10045.4.3.4" => ECDSAWithSha512,
+                "1.2.840.113549.1.1.1" => RSA,
+                "1.2.840.113549.1.1.5" => RSAWithSha1,
+                "1.2.840.113549.1.1.7" => RSAOAEP,
+                "1.2.840.113549.1.1.8" => MGF1,
+                "1.2.840.113549.1.1.9" => OaepPSpecified,
+                "1.2.840.113549.1.1.10" => RSAPSS,
+                "1.2.840.113549.1.1.11" => RSAWithSha256,
+                "1.2.840.113549.1.1.12" => RSAWithSha384,
+                "1.2.840.113549.1.1.13" => RSAWithSha512,
+                "1.2.840.113549.1.5.3" => PbeWithMD5AndDESCBC,
+                "1.2.840.113549.1.5.10" => PbeWithSha1AndDESCBC,
+                "1.2.840.113549.1.5.11" => PbeWithSha1AndRC2CBC,
+                "1.2.840.113549.1.5.12" => Pbkdf2,
+                "1.2.840.113549.1.5.13" => PasswordBasedEncryptionScheme2,
+                "1.2.840.113549.1.7.1" => Pkcs7Data,
+                "1.2.840.113549.1.7.2" => Pkcs7SignedData,
+                "1.2.840.113549.1.7.3" => Pkcs7EnvelopedData,
+                "1.2.840.113549.1.7.6" => Pkcs7EncryptedData,
+                "1.2.840.113549.1.9.1" => Pkcs9EmailAddress,
+                "1.2.840.113549.1.9.3" => Pkcs9ContentType,
+                "1.2.840.113549.1.9.4" => Pkcs9MessageDigest,
+                "1.2.840.113549.1.9.5" => Pkcs9SigningTime,
+                "1.2.840.113549.1.9.6" => Pkcs9CounterSigner,
+                "1.2.840.113549.1.9.7" => Pkcs9Challenge,
+                "1.2.840.113549.1.9.14" => Pkcs9ExtensionRequest,
+                "1.2.840.113549.1.9.15" => Pkcs9SMimeCapabilities,
+                "1.2.840.113549.1.9.16.1.4" => TstInfo,
+                "1.2.840.113549.1.9.16.2.12" => SigningCertificateAttr,
+                "1.2.840.113549.1.9.16.2.14" => SignatureTimeStampAttr,
+                "1.2.840.113549.1.9.16.2.47" => SigningCertificateV2Attr,
+                "1.2.840.113549.1.9.20" => Pkcs9FriendlyName,
+                "1.2.840.113549.1.9.21" => LocalKeyId,
+                "1.2.840.113549.1.9.22.1" => Pkcs12X509CertType,
+                "1.2.840.113549.1.12.1.3" => Pkcs12TripleDes,
+                "1.2.840.113549.1.12.1.5" => Pkcs12Rc2Cbc128,
+                "1.2.840.113549.1.12.1.6" => Pkcs12Rc2Cbc40,
+                "1.2.840.113549.1.12.10.1.1" => Pkcs12KeyBag,
+                "1.2.840.113549.1.12.10.1.2" => Pkcs12ShroudedKeyBag,
+                "1.2.840.113549.1.12.10.1.3" => Pkcs12CertBag,
+                "1.2.840.113549.1.12.10.1.5" => Pkcs12SecretBag,
+                "1.2.840.113549.1.12.10.1.6" => Pkcs12SafeContentsBag,
+                "1.2.840.113549.2.5" => MD5,
+                "1.2.840.113549.2.7" => HMACSHA1,
+                "1.2.840.113549.2.9" => HMACSHA256,
+                "1.2.840.113549.2.10" => HMACSHA384,
+                "1.2.840.113549.2.11" => HMACSHA512,
+                "1.2.840.113549.3.2" => RC2CBC,
+                "1.2.840.113549.3.7" => TripleDESCBC,
+                "1.3.6.1.4.1.311.17.1" => Pkcs12KeyProviderName,
+                "1.3.6.1.4.1.311.17.3.20" => KeyIdentifier,
+                "1.3.6.1.4.1.311.20.2.3" => UserPrincipalName,
+                "1.3.6.1.4.1.311.88.2.1" => DocumentNameAttr,
+                "1.3.6.1.4.1.311.88.2.2" => DocumentDescriptionAttr,
+                "1.3.6.1.5.5.7.3.1" => KeyPurposeTlsServer,
+                "1.3.6.1.5.5.7.3.2" => KeyPurposeTlsClient,
+                "1.3.6.1.5.5.7.3.3" => KeyPurposeCodeSign,
+                "1.3.6.1.5.5.7.3.4" => KeyPurposeEmailProtection,
+                "1.3.6.1.5.5.7.3.8" => KeyPurposeTimestamping,
+                "1.3.6.1.5.5.7.3.9" => KeyPurposeOcspSigner,
+                "1.3.6.1.5.5.7.6.2" => Pkcs7NoSignature,
+                "1.3.6.1.5.5.7.48.1" => OCSP,
+                "1.3.6.1.5.5.7.48.1.2" => OcspNonce,
+                "1.3.6.1.5.5.7.48.2" => CAIssuers,
+                "1.3.14.3.2.26" => SHA1,
+                "1.3.14.3.2.7" => DES,
+                "1.3.132.0.34" => Secp384r1,
+                "1.3.132.0.35" => Secp521r1,
+                "2.5.4.3" => CommonName,
+                "2.5.4.5" => SerialNumber,
+                "2.5.4.6" => CountryOrRegionName,
+                "2.5.4.7" => Locality,
+                "2.5.4.8" => StateOrProvinceName,
+                "2.5.4.10" => OrganizationName,
+                "2.5.4.11" => OrganizationalUnit,
+                "2.5.4.97" => OrganizationIdentifier,
+                "2.5.29.14" => SubjectKeyIdentifier,
+                "2.5.29.15" => KeyUsage,
+                "2.5.29.17" => SubjectAlternativeName,
+                "2.5.29.19" => BasicConstraints,
+                "2.5.29.20" => CrlNumber,
+                "2.5.29.35" => AuthorityKeyIdentifier,
+                "2.16.840.1.101.3.4.1.2" => Aes128Cbc,
+                "2.16.840.1.101.3.4.1.22" => Aes192Cbc,
+                "2.16.840.1.101.3.4.1.42" => Aes256Cbc,
+                "2.16.840.1.101.3.4.2.1" => Sha256,
+                "2.16.840.1.101.3.4.2.2" => Sha384,
+                "2.16.840.1.101.3.4.2.3" => Sha512,
+                "2.23.140.1.2.1" => CabForumDV,
+                "2.23.140.1.2.2" => CabForumOV,
+                _ => ReadOnlySpan<byte>.Empty,
+            };
+        }
+    }
+}
+#endif